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Why encode data?. Three reasons to encode data that is about to be transmitted(through space) or stored(in a computer):1. For efficiency (Information Theory)2. For error detection/correction (Coding Theory)3. For secrecy/authentication (Cryptography) (use
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1. Coding Theory Rong-Jaye Chen
2. Why encode data? Three reasons to encode data that is about to be transmitted(through space) or stored(in a computer):
1. For efficiency (Information Theory)
2. For error detection/correction (Coding Theory)
3. For secrecy/authentication (Cryptography)
(use “encrypt data” instead of “encode data”)
3. Why coding theory? For example, to send CODES(source message)
1. Encoding for efficiency(after Huffman encoding)
00000/1001/10100/010/0011 000/001/001/101/000/100/011(source strings)
2. Encoding for correction
C: binary [5,3]-code with generator matrix G
G = 1 1 1 1 1
1 0 1 0 1
0 0 1 1 0
4. Why coding theory? Example:
encode string s = 111 to
codeword c = sG = 01100
As a result we encode
000/001/001/101/000/100/011(source strings) as
00000/00110/00110/11001/00000/11111/10011(codewords)
If c’ = 01100 is received(with no error)
sG = c’ => solve linear system => s = 111
5. Why coding theory? If the received word c’=c+e contains error e then we wish it will be detected(then we can do retransmission) or even better corrected as c.
Goal: Design a good code C
6. Why coding theory?
Read “Coding theory: the first 50 years”
-- by Richard Pinch
( http://plus.maths.org/issue3/codes/)
7. Texts 1. Coding Theory & Cryptography
The Essentials
2nd Edition, Revsed and Expanded
Marcel Dekker, Inc.
by Hankerson, Hoffman, Leonard, Lindner
Phelps, Rodger, Wall
8. Texts 2. Coding Theory
A First Course
Cambridge University Press 2004
by San Ling and Chaoping Xing
9. 1.Coding Theory & Cryptographythe Essentials by H2L2PRW Part I: Coding Theory
1. Intro to Coding Theory
2. Linear Codes
3. Perfect and Related Codes
4. Cyclic Linear Codes
5. BCH Codes
6. Reed-Solomon Codes
7. Burst Error-Correcting Codes
8. Convolutional Codes
9. Reed-Muller and Preparata Codes
10. Part II: Cryptography(not included in the course)
10. Classical Cryptography
10.1 Encryption schemes
10.2 Symmetric-key encryption
10.3 Feistel ciphers and DES
11. Topics in Algebra and Number Theory
11.1 Algorithms, complexity, and modular arithmetic
11.2 Quadratic residues
11.3 Primality testing
11.4 Factoring and square roots
11.5 Discrete logarithms
12. Public-key Cryptography
12.1 One-way and hash functions
12.2 RSA
12.3 Provable security
12.4 ElGamal
12.5 Cryptography protocols
11. 2.Coding Theory – A First Course by Ling & Xing 1. Introduction
2. Error detection, correction and decoding
3. Finite fields
4. Linear codes
5. Bounds in coding theory
6. Constructions of linear codes
7. Cyclic codes
8. Some special cyclic codes
9. Goppa Codes
12. Math involved in Coding theory
Probability
Combinatorics
Linear Algebra
Finite Field